In the related art, it is proposed that, between AC-coupled apparatuses, charges are fed from a potential setting unit before transmitting a differential signal such that a signal line pair has stable potential, and dummy pattern data is transmitted until an amplitude of a differential signal reaches a specified amplitude value (for example, see Patent Literature 1).
In addition, the Embedded DisplayPort (hereinafter referred to as eDP) standard, which becomes popular in recent years, has a function of Advanced Link Power Management (ALPM). The ALPM is a function to decrease a power consumption by suspending transmission processing of a Main Link when no transmission data is present.
Here, the Main Link is a channel mainly used for a transmission of data to be processed in each apparatus among a plurality of channels for a signal transmission between apparatuses.
In the ALPM, an AUX_PHY_WAKE signal is transmitted from a transmission side to a reception side via an AUX CH separately provided from the Main Link before the transmission of a Main Link signal is restarted. The reception side restarts reception processing of the Main Link triggered by the reception of the AUX_PHY_WAKE signal.
Here, the AUX CH is a channel mainly used for a transmission of a control signal among the plurality of channels for the signal transmission between the apparatuses.
Incidentally, AC coupling is used for connecting the Main Link between the apparatuses in conformity with the eDP standard. Accordingly, in a case where transmission processing of the Main Link is restarted, it is necessary to sufficiently charge a capacitance (e.g., capacitor) for the AC coupling and to stabilize the potential of signal lines of the Main Link, for example, using the method described in Patent Literature 1.